Dr. Britt Faucette, PhD, CPESC, LEED AP Ecosystem Scientist. Designing with Nature: Compost Blankets & Filter Socks for Erosion & Sediment Control

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1 Dr. Britt Faucette, PhD, CPESC, LEED AP Ecosystem Scientist Designing with Nature: Compost Blankets & Filter Socks for Erosion & Sediment Control

2 Stormwater Impact US cities w/ outdated & under-designed SWM infrastructure 75% of Americans live near polluted waters $44,000,000,000 annual total cost to society

3 Land Use - Water Cycle LID Filtrexx Products 2004 Source: Sego Jackson, 2001

4 Erosion Control/ Soil Stabilization BMPs Hydroseed Hydraulic Mulches Straw Mulch RECPs: straw, coconut, jute, excelsior RECPs: single and double net Tackifiers Polyacrylamide (PAMs)

5 Natural Stormwater Management Source: Sego Jackson

6 Compost Tools Filter Media Growing Media Designed for Optimum Filtration & Hydraulic-flow Designed for Optimum Water Absorption & Plant Growth

7 Stormwater BMPs Erosion & Sediment Control 1. Perimeter Control 2. Inlet Protection 3. Ditch Check 4. Filter Ring/Concrete Washout 5. Slope Interruption 6. Runoff Diversion 7. Vegetated Cover 8. Erosion Control Blanket 9. Vegetated Sediment Trap 10. Pond Riser Pipe Filter Low Impact Development 11. Runoff Control Blanket 12. Vegetated Filter Strip 13. Engineered Soil 14. Channel Liner 15. Streambank Stabilization 16. Biofiltration System 17. Bioretention System 18. Green Roof System 19. Living Wall 20. Green Retaining Wall 21. Vegetated Rip Rap 22. Level Spreader 23. Green Gabion 24. Bioswale

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9 Runoff + Erosion Control Designed to: 1) dissipate energy of rain impact; 2) hold, infiltrate & evaporate water; 3) slow down/disperse energy of sheet flow; 4) provide for optimum vegetation growth

10 Particle Size Matters Treatment Soil Loss (kg ha -1 ) TSS (kg ha -1 ) Turbidity (NTU) Particle size % passing 1 in 1/2 in 1/4 in Compost Compost 2* Compost 3* Compost 4** *Did not meet TX DOT specification for erosion control compost particle size distribution. **Did not meet TX DOT, USEPA, IN DNR, or CONEG specification for erosion control blanket particle size distribution

11 Total Soil Loss Hydromulch vs Compost Blanket: Two 3 /hr storm events Day 1 = 2,750 & 1,230 lb/ac 3 mo = 1,960 & 115 lb/ac

12 Turbidity (NTU) Average from 4 inch Storm Event x x 0 Straw /Pam Compost-Coarse Compost-Fine

13 Soil Erosion at 2:1 Erosion Control Practice Soil 2 in/hr 20 min (0.67 in) Soil 4 in/hr 40 min (2.0 in) Soil 6 in/hr 60 min (4.0 in) t/ac % reduction t/ac % reduction t/ac % reduction Bare soil 61 NA 137 NA 171 NA CECB 2.0 in CECB 1.0 in CECB 0.5 in Single-net straw Single-net excelsior fiber Double-net straw Double-net coconut fiber Tackifier PAM

14 Design: CECB Thickness based on Slope Angle ( ) Slope & 24 Rainfall Total Rainfall = 1.0 in Rainfall = 2.0 in Rainfall = 4.0 in 4:1 ½ in 2 in 2 in 3:1 ½ in 1 in 2 in 2:1 1 in 1 in 1 in

15 Compost Blanket Hydroseeding Demo Project in Atlanta after 3 storm event

16 LID: Rainfall Absorption (4 /hr 1-hr; 100 yr return) 84% % % 0 Bare Soil Straw Mulch Compost Blanket

17 Runoff Volume Reduction Reduction Influencing Factors Reference 49% 60% 76% 90% Sandy clay loam, 10% slope, 1.5 blanket, 3.2 in/hr 1 hr rain Sandy clay loam, 10% slope, 1.5 blanket, 4.0 in/hr 1 hr rain Silty sand, 2:1 slope, 3 blanket, 1.8 in/hr hr rain Loamy sand, 3:1 slope, 2 blanket, 4.0 in/hr 2 hr rain Faucette et al, 2005 Faucette et al, 2007 Demars et al, 2000 Persyn et al, 2004

18 Peak Flow Rate Reduction Reduction Influencing Factors Reference 36% 42% (30% relative to straw) 79% Sandy clay loam, 10% slope, 1.5 blanket, 3.2 in/hr 1 hr rain Sandy clay loam, 10% slope, 1.5 blanket, 4.0 in/hr 1 hr rain Loamy sand, 3:1 slope, 2 blanket, 4.0 in/hr 2 hr rain Faucette et al, 2005 Faucette et al, 2007 Persyn et al, 2004

19 *Based Hydrologic Soil Group B Reference: USDA SCS, 1986 Runoff Curve Numbers Watershed Surface Curve Number* Parking lot, driveway, roof 98 Commercial district 92 Dirt road 82 Residential lot: ¼ ac, ½ ac, 1 ac 75, 70, 68 Cropland Pasture Public green space Woodland and forests Brush >75% cover 48 Vegetated Compost Blanket 55

20 Pollutant Load Reduction: Compost Blanket vs Conventional Seeding Mukhtar et al, 2004 (seed+fertilizer) Faucette et al, 2007 (seed+fertilizer) Faucette et al, 2005 (hydromulch) Persyn et al 2004 (seed+topsoil) Total N Nitrate N Total P Soluble P Total Sediment 88% 45% 87% 87% 99% 92% ND ND 97% 94% 58% 98% 83% 83% 80% 99% ND 99% 99% 96%

21 Sediment Control/ Stormwater Filter BMPs Silt Fence Straw Bale Mulch Berm Fiber Rolls Straw Wattles Filtration Systems Chemical Treatment Stormwater Ponds

22 Compost Tools Filter Media Growing Media Designed for Optimum Filtration & Hydraulic-flow Designed for Optimum Water Absorption & Plant Growth

23 Stormwater BMPs Erosion & Sediment Control 1. Perimeter Control 2. Inlet Protection 3. Ditch Check 4. Filter Ring/Concrete Washout 5. Slope Interruption 6. Runoff Diversion 7. Vegetated Cover 8. Erosion Control Blanket 9. Sediment Trap 10. Pond Riser Pipe Filter Low Impact Development 11. Runoff Control Blanket 12. Vegetated Filter Strip 13. Engineered Soil 14. Channel Liner 15. Streambank Stabilization 16. Biofiltration System 17. Bioretention System 18. Green Roof System 19. Living Wall 20. Green Retaining Wall 21. Vegetated Rip Rap 22. Level Spreader 23. Green Gabion 24. Bioswale

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25 Natural Stormwater Management Source: Sego Jackson

26 Bacteria Compost Sock 3-Way Filtration Fungi Physical Traps sediment in matrix of varying pore spaces and sizes Chemical Binds and adsorbs pollutants in storm runoff Biological Degrades various compounds with bacteria and fungi Filtrexx Products 2004

27 Particle Size Specifications

28 Removal (%) TSS Removal for Sediment Control Barriers " Compost Filter Sock 12" Compost Filter Sock Runoff Volume: 315 gal 42 ft gal/ft ac-in Sediment: 15 lbs 6000 mg/l Sediment Barrier Mulch Filter Berm Straw Bale

29 Runoff Exposure Sediment Exposure Removal Compost Sock 260 gal 1.7 g/ft ac-in 850 lbs 150 lbs/ft t/a 77% Silt Fence 260 gal 1.7 g/ft ac-in 850 lbs 150 lbs/ft t/a 72% Straw Wattle 260 gal 1.7 g/ft ac-in 850 lbs 150 lbs/ft t/a 59% ASTM 6459 for RECPs

30 Storm Water Pollutant Removal TSS Turbidity Total N NH4 -N NO3 -N Total P Sol. P Total coli. E. coli. Metals Oil Diesel Filter Sock 80 % 63 % 35 % 35 % 25 % 60 % 92 % 98 % 98 % % 99 % 99 %

31 City of Chattanooga Analysis (Preretrofit) COD 1600 mg/l TSS 1370 mg/l Oil/Grease 107 mg/l mg/l 208 mg/l 27 mg/l mg/l 125 mg/l 125 mg/l mg/l mg/l mg/l N/A N/A 5 mg/l mg/l 249 mg/l 18 mg/l mg/l 177 mg/l 37 mg/l % Reduction

32 The Sustainable BMP 100% Recycled (compost) Bio-based, organic materials Locally manufactured Reduces Carbon Footprint Uses Natural Principles (Natural Capital & Ecosystem Services) High Performance

33 Real Value of LID National average real estate values down 25% from 2007 (-$82,000) Low Impact Development Sites: $ $5000 more/lot $4000 less cost/lot 25-30% less cost/lot 15% - water quality 6% - green infrastructure 5% - reduce flooding in flood plain 33-50% energy savings (Source: NCSU)

34 Britt Faucette, Ph.D., CPESC, LEED AP Ecosystem Scientist Ph:

35 Runoff Coefficients Watershed Surface Asphalt, concrete, rooftop, downtown area 0.95 Neighborhood, apartment homes 0.7 Single family home site 0.5 Coefficient Bare graded soil clay, silt, sand 0.6, 0.5, 0.3 Lawn, pasture Undisturbed forest 0.15 Compost blanket (0.28) Reference: GA Storm Water Management Manual, 2001

36 Results: CECB Thickness & Slope Steepness CECB Thickness (in) Slope Angle (H:V) Soil 2 in/hr 20 min (0.67 in) Soil 4 in/hr 40 min (2.0 in) Soil 6 in/hr 60 min (4.0 in) t/ac % reduction t/ac % reduction t/ac % reduction Bare soil 2:1 61 NA 137 NA 171 NA 2.0 2: : : Bare soil 3:1 55 NA 132 NA 144 NA 2.0 3: : : Bare soil 4:1 72 NA 108 NA 110 NA 2.0 4: : :

37 USLE C Factors A= R x K x LS x C x P Erosion Control Bare Soil 1.0 Wood Mulch Straw Mulch Compost Blanket C Factor Reference Demars and Long, 1998; Faucette et al, 2004 Demars and Long, 1998; Faucette et al, 2006 Forest floor GA SWCC, 2000 Mukhtar et al, 2004; Demars and Long, 1998; Demars et al, 2000; Faucette et al 2005; Faucette et al, 2006

38 Sediment Removal Efficiency (%) Fine Sediment Removal FilterSoxx Fine Sediment Removal over 30 min Runoff Event A f t e r B e f o r e Silt Clay min 10 min 20 min 30 min Class 1: 0.01 um um Class 2: um um

39 Hydraulic Design Capacity of Filter Socks & Silt Fence in Runoff Control Applications H. Keener, B. Faucette, M. Klingman Flow through rates were 50% greater for filter socks 12 Compost sock = 24 silt fence; 18 Compost sock = 36 silt fence gpm/ft

40 Filter Sock Design Tool

41 Low Impact Development (LID) = Source: Sego Jackson restore natural site hydrology; decentralize

42 Compost + Additives To target specific runoff pollutant Nutrients (N & P) Bacteria Metals Petroleum Hydrocarbons

43 Compost Filter Socks: Green Infrastructure & Stormwater Quality Britt Faucette, Ph.D., CPESC, LEED AP Ecosystem Scientist

44 Silt Fence vs Compost Berm Mean Total Solids Load for 3 Storm Events grams/m % All Plots used Hydromulching 0 Silt Fence Filter Berm Nutrient Loads for 2nd Storm Event mg/m % -32% 0 Silt Fence Total N Total P Filter Berm

45 Sediment Summary % Reduction of TSS & Turbidity Treatment TSS Turbidity Silt Fence Filter Sock * Based on rainfall of 3.0 in/hr for 30 min; runoff sediment concentration (sandy clay loam) of 70,000 mg/l.

46 RECP + Hydromulch Compost Blanket Compost Fills in the Low Spaces

47 Low Impact Development (LID) = hydrology mimics natural site, distributed, decentralized Runoff Volume Runoff Rate Pollutant Loading Flooding Water Quality Wildlife Habitat/Biodiversity Aesthetics/Land Value Green Infrastructure = green stormwater management; site Source: Sego Jackson preservation/restoration; integrated design & practices; reuse

48 Filtration Devices use Filter Media